Research news

SNPs (single nucleotide polymorphisms) are valuable markers for mapping mutations
and human disease-related genes. In the June issue of Nature Genetics, Wicks et al. describe a SNP-based strategy for rapid mapping in the C. elegans genome (Nature Genetics 2001, 28:160-164). They sequenced the entire genome of the CB4856 Hawaiian worm isolate and compared it with the standard laboratory wild type strain (Bristol N2). This
alignment identified 6,222 potential polymorphisms, more than half of which modify
restriction enzyme sites (referred to as 'snip-SNPs'). Such a high-density map of
snip-SNPs (about one every 200 kb) allows for rapid mapping of gene mutations using
RFLP analysis. To demonstrate the efficiency of such a mapping approach, Wicks et al. used their snip-SNP map and bulked segregant analysis to localize the dyf-5 gene. They claim that the successful mapping could be achieved with 36 PCR reactions
within 12 hours of isolating F2 animals from a single cross between CB4856 and N2
strains.

References

Prospects for whole-genome linkage disequilibrium mapping of common disease genes.